Trigger mechanism for a firearm



Feb. 2, 1965 F. G. JUNGELING 3,167,877

TRIGGER MECHANISM FOR A FIREARM Filed Nov. 8, 1962 2 Sheets-Sheet 1 ll///// I//// ///4 a ll INVENTOR FRIEDHELM 6. aoueauNe ATTORNEYS Feb. 2, 1965 F. s. JUNGELING TRIGGER MECHANISM FOR A FIREARM 2 Sheets-Sheet 2 Filed Nov. 8, 1962 FREDHELM s. JUNGEUNG ATTORNEYS United States Patent "'ce 3,167,877 TRIGGER MECHANISM FOR A FIREARM Friedhelm G. Jiingeling, Amsterdam, Netherlands, assignor to Staatsbedrijf Artillerie-Inrichtingen, Hembrug-Zaandam, Netherlands, a corporation of the Netherlands Filed Nov. 8, 1962, Ser. No. 236,351 Claims priority, application Netherlands, Nov. 22, 1961, 271,660 3 Claims. (Cl. 4269) The invention relates to a trigger mechanism for a rifle or like firearm, having the trigger loaded by a spring and maintained by said spring, in an inoperative position with its arm on an abutment face, said trigger being rotatable about an axis, on which a lever or sear is rotatably supported and slidable in longitudinal direction, said lever having its one arm cooperating with a cam on the hammer loaded by a spring for locking the hammer and its other arm being adapted to engage a projection on the arm of the trigger. With said position of the lever, which it reaches after firing the shot and the return stroke of the guide body caused thereby, the spring of the hammer will tend to urge the lever backwards when the guide body moves forwards again and releases the hammer, so that the lever is clamped on the projection of the trigger arm. When the trigger is released the trigger arm moves downwards under the action of the trigger spring and said arm has to release the lever.

With the above described construction of the trigger mechanism the drawback is encountered that when the sear adheres to the projection on the trigger arm due to dirt in the mechanism the trigger does not disengage the sear so that the operation is disturbed.

The invention has for its object to remove said drawback and according to the invention the sear at its end remote from the hammer is provided with a projection slidable against spring pressure. For the same purpose the projection on the trigger arm cooperating with said sear may be slidable against the pressure of a spring. Due to pressure exerted on the sear by the spring of the hammer said spring loaded projection will be displaced against the pressure of its spring until the sear contacts the axis of the trigger, so that now the pressure exerted by the hammer spring on the sear is taken up by said axis and the sear at its end engaging the trigger arm will only be subjected to the pressure of the spring loaded projection.

The invention will be further described with reference to the accompanying drawing showing two embodiments of the trigger mechanism.

In the drawing FIG. 1 is a side view of the trigger mechanism according to a first embodiment with part in section, the spring loaded slidable projection being mounted into the end of the trigger lever and the mechanism is shown with the trigger in its neutral position.

FIG. 2 is a plan view of the mechanism shown in FIG. 1, the hammer being omitted.

FIGS. 3 and 4 are similar views as FIG. 1 with the mechanism in two other positions.

FIG. 5 is a side view with part in section of a triggermechanism according to a second embodiment having the slidable projection constituted by a portion of a spring mounted on the trigger arm and bent from wire.

FIG. 6 is a plan view of the trigger shown in FIG. 5.

The hammer 1 is rotatably supported on a pin 2 through the intermediary of a hollow journal 3 extending on both sides of the hammer, said pin being secured in the receiver of the barrel. The trigger 4 is rotatably supported on a fixed axis 5 and is in its inoperative postion shown in FIG. 1 urged downwards with its arm 8 on an abutment face 7 at the bottom of the receiver under the in- 3,167,877 Patented Feb. 2, 1965 fiuence of a spring 6 bent to a U-shape. In both-legs of spring 6 some coils are formed, which are placed on journals 9 extending on both sides of the trigger 4. The ends 10 of both legs of spring 6 bear on the bottom of the receiver.

On the axis 5 of the trigger 4 lever or sear 12 is supported by means of an oblong opening 11 so that the sear can be displaced in longitudinal direction. The arm 8 of the trigger contains a slidable stud 13 loaded by a spring 14 which at its other end bears against a threaded pin 15 screwed in the trigger arm 8. Stud 13 urges on a fixed projection 16 provided on the seat 12.

A slidable stud or plunger 18 is mounted in the arm 17 of sear 12 remote from the hammer 1 and said stud is loaded by a spring 19 tending to urge the stud outwards. The displacement of stud 18 is restricted by an abutment pin 20.

The hammer 1 is actuated by a U-shaped spring 21 tending to rotate the hammer in anti-clockwise direction and in each leg of said spring some coils 22 are formed, said coils being placed on journals 3 extending on both sides of the hammer. The legs 23 of spring 21 are each bearing on the axis 5 of the trigger.

If in the position of the mechanism shown in FIG. 1 in which the spring 6 has only a slight pre-tension, the trigger is pulled the arm 8 of the trigger strikes the abutment face 24 which e.g. may be provided on a fire regulater. The trigger arm 8 thereby urges the rear arm 17 of sear 12 upwards so that said sear with its other arm disengages the cam 25 on the hammer 1, whereby the stud 13 bearing on the projection 16 of sear 12 will displace said sear forwards to the dotted line position indicated in FIG. 1. The hammer 1 is now released and strikes the striking pin 26 as shown in dotted lines in FIG. 1, so that the shot is fired. The guide body of which part is shown at 27 in FIG. 3 now moves backwards under the influence of the gas pressure, so that the hammer 1 swings to the position shown in FIG. 3. Thereby the spring loaded stud 13 of the trigger arm 8 will rotate sear 12, so that the latter reaches the position shown in FIG. 3 between cam 25 on the hammer 1 and the projection 28 on the trigger arm 8. As new the guide body 27 moves forward again, the hammer 1 is released until its cam 25 strikes the foremost end of sear 12 and under the action of its spring 21 moves the sear 12 backwards to the position shown in FIG. 4, in which the spring loaded stud 18 is depressed. As sear 12 now contacts the front side of the trigger axis 5 the pressure of the hammer spring 21 is taken up by said axis and the projection 28 of the trigger arm 8 is only loaded by the slight pressure of the spring 19 of stud 18. If now the trigger is released the arm 8 of the trigger under the influence of the tension of spring 6 strikes on the abutment face 7 and disengages sear 12, so that the stud 18 slides outwards on the arm 8 of the trigger and the mechanism again reaches its initial position shown in FIG. 1.

With the embodiment according to FIGS. 5 and 6 the spring loaded stud 18 on the sear 12 is replaced by a leg 30 of a spring 29 bent from wire and mounted on the trigger arm 8 in such a manner that the spring embraces a pin 31 extending through the trigger arm 8, the spring with its ends engages a pin 32 also projecting from arm 8. The position of the mechanism shown in FIG. 5 is the neutral position corresponding to that shown in FIG. 1. The operation of said embodiment fully corresponds to that of the mechanism described With reference to FIGS. 1-4, so that after firing the shot the rearmost end of sear 12 urges against leg 30 of spring 29 and the pressure of the spring 21 of hammer 1 is taken up by the trigger axis 5.

What I claim is: a

1. A trigger mechanism for a firearm, such as a rifle, comprising a trigger having a rearwardly extending arm and mounted for rotation about a pivot axle, a projection on said arm spaced rearwardly of said axle, a stationary abutment for engagement with said arm to limit rotational movement of the trigger, a spring urging said trigger to an inoperative position with its arm engaging said abutment, a sear supported on said axle for rotation and sliding movement longitudinally of said arm, a hammer, a cam on said hammer, a spring urging said hammer toward firing condition, said sear having a first arm cooperating with said cam to lock said hammer in a non-firing condition, a second 'arm on said sear having a portion engageable with said projection on the trigger arm, and a spring urging said portion of the second arm of the sear into engagement with said projection'on'the arm of the trigger, said sear when in position for engagement with the projection on the trigger arm being prevented from further longitudinal rearward movement by the trigger axle.

2. A trigger mechanism for a firearm according'to claim 1, wherein said portion of the second sear arm engageable with the trigger arm projection constitutes the rear face of said second arm and the spring urging said portion is fastened to the trigger and includes a leg engageable with the rear face of the second arm of the sear.

3. A trigger mechanism according to claim 1, wherein said portion of the second sear arm engageable with the trigger arm projection constitutes a s-lideable plunger urged to project rearwardly from the rear face of the second arm of the sear 'by said spring.

References Cited by the Examiner UNITED STATES PATENTS 3,015,993 1/62 Franchi 89-140 X BENJAMIN A. BORCHELT, Primary Examiner. 

1. A TRIGGER MECHANISM FOR A FIREARM, SUCH AS A RIFLE, COMPRISING A TRIGGER HAVING A REARWARDLY EXTENDING ARM AND MOUNTED FOR ROTATION ABOUT A PIVOT AXLE, A PROJECTION ON SAID ARM SPACED REARWARDLY OF SAID AXLE, A STATIONARY ABUTMENT FOR ENGAGEMENT WITH SAID ARM TO LIMIT ROTATIONAL MOVEMENT OF THE TRIGGER, SPRING URGING SAID TRIGGER TO AN INOPERATIVE POSITION WITH ITS ARM ENGAGING SAID ABUTMENT, A SEAR SUPPORTED ON SAID AXLE FOR ROTATION AND SLIDING MOVEMENT LONGITUDINALLY OF SAID ARM, A HAMMER, A CAM ON SAID HAMMER, A SPRING URGING SAID HAMMER TOWARD FIRING CONDITION, SAID SEAR HAVING A FIRST ARM COOPERATING WITH SAID CAM TO LOCK SAID HAMMER IN A NON-FIRING CONDITION, A SECOND ARM ON SAID SEAR HAVING A PORTION ENGAGEABLE WITH SAID PROJECTION ON THE TRIGGER ARM, AND A SPRING URGING SAID PORTION OF THE SECOND ARM OF THE SEAR INTO ENGAGEMENT WITH SAID PROJECTION ON THE ARM OF THE TRIGGER, SAID SEAR WHEN THE POSITION FOR ENGAGEMENT WITH THE PROJECTION ON THE TRIGGER ARM BEING PREVENTED FROM FURTHER LONGITUDINAL REARWARD MOVEMENT BY THE TRIGGER AXLE. 